The present invention relates to crystal oscillators for use in electronic equipment such as communication devices.
Turning now to FIGS. 8 and 9, there is shown a conventional crystal oscillator 90 comprises a casing or housing 51 having a recess 52. A vibrating plate 53 is housed within the recess 52. The right edge 54 of the plate 53 is fixed or mounted within the recess 52 to the housing 51 by means of conductive adhesive layers 55, 56. The vibrating plate is sandwiched between a pair of electrodes 57, 58. A right-side electrical terminal 59 and a left-side electrical terminal 60 are formed on the surfaces of the housing 51. The conductive layer 55 is used to electrically connect the upper electrode 57 to the right-side electrical terminal 59. The conductive layer 56 is used to electrically connect the lower electrode 58 to the left-side electrical terminal 60. An upper casing or plate 61 is bonded to the upper surface 62 of the lower housing 51 sealing the vibrating plate 53 mounted in the recess of said lower housing.
The dimensions of the conventional crystal oscillator 90 shown in FIGS. 8 and 9 are small. As a result, extreme care must be used in mounting the vibrating plate 53 in an exact position within the recess 52. Unless extreme care is used in mounting the vibrating plate 53, the plate may be improperly attached to or misaligned in the lower housing 51, causing the vibrating plate 53 to contact the lower housing 51 or the upper plate 61 thereby, producing unstable or irregular oscillations of the vibrating plate 53.
The process of fabricating the conventional crystal oscillator 90 is further complicated by the plurality of bends required to form the right and left-side electrical terminals to provide continuous connections from the adhesive layers 55, 56 within the recess 52 to the external side surfaces of the lower housing 51.